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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        
    </style>
</head>
<body>
    
</body>
<script>
    // class Person{
    //     static [Symbol.hasInstance](param){
    //         console.log(param)
    //         console.log("我被用来检测类型了")
    //     }
    // }
    // let o={};

    // console.log(o instanceof Person)

    const arr=[1,2,3]
    const arr2=[4,5,6]
    console.log(arr.concat(arr2))
</script>
</html>